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Journal of Applied Electrochemistry

, Volume 32, Issue 2, pp 149–156 | Cite as

Effect of temperature on stability of adsorbed inhibitors on steel in phosphoric acid solution

  • M.A. AmeerEmail author
  • E. Khamis
  • G. Al-Senani
Article

Abstract

Rates of steel dissolution in 35% H3PO4/6% butanol (test solution) in the presence of thiosemicarbazide and seven of its derivatives were determined by spectrophotometry, weight loss and potentiodynamic and impedance techniques in the temperature range 303 to 333 K. At all temperatures, the corrosion rate decreased with increasing inhibitor concentration. Increasing temperature decreased the protection efficiency particularly at concentrations less than 2.5 × 10−4 M. At inhibitor concentrations above 2.5 × 10−4 M, increasing the temperature did not affect efficiency. Potentiodynamic polarization measurements indicated that the inhibitors have a strong effect on the corrosion behavior of the steel and behave as mixed type inhibitors. Thermodynamic functions obtained from this study indicate that the presence of the inhibitors increase the activation energy. The negative values of ΔG* indicated spontaneous adsorption on the metal surface. A kinetic-thermodynamic model was found to describe the experimental well data at different temperatures.

adsorption isotherm inhibitor molecular structure phosphoric acid steel temperature thiosemicarbazide 

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References

  1. 1.
    E. Khamis, M. Ameer, N. AlAndis and G. Al-Senani, Corrosion 56 (2000) 127.Google Scholar
  2. 2.
    M. Ameer, E. Khamisand G. Al-Senani, Adsorption Sci. & Technol. 18 (2000) 2.Google Scholar
  3. 3.
    I.N. Putilova, S.A. Balezin and V.P. Barannik, ‘Metallic Corrosion Inhibitors’ (Pergamon Press, New York, 1960), p. 55.Google Scholar
  4. 4.
    W.S. Calcott and J.C. Whetzel, Trans. Am. Inst. Chem. Eng. 35 (1923) 1.Google Scholar
  5. 5.
    S.V. Gorbachev, Zh. Fiz. Khim 24 (1950) 888.Google Scholar
  6. 6.
    S.V. Gorbachev and R.M. Vasenin, Zh. Fiz. Khim. (Russia) 28 (1954) 135.Google Scholar
  7. 7.
    A.V. Izmailov, Zh. Fiz. Khim. (Russia) 30 (1956) 2813.Google Scholar
  8. 8.
    W. Machu, Korros. u. Metalls. 14 (1938) 324.Google Scholar
  9. 9.
    T. Sydberger and S. Nordin, Corrosion 34 (1978) 16.Google Scholar
  10. 10.
    B. Abd El-Nabey, E. Khamis, G. Thompson and J. Dawson. Surf. Coat. Technol. 28 (1986) 83.Google Scholar
  11. 11.
    E. Khamisand A. Hosny, Adsorption Sci. & Technol. 12 (1995) 67.Google Scholar
  12. 12.
    E. Khamis, A. Hosny and S. El-Hadary, Afinidad 456 (1995) 95.Google Scholar
  13. 13.
    H.A. Al-Lohedan, E. Khamis and Z.A. Issa, Adsorption Sci. & Technol. 13 (1996) 137.Google Scholar
  14. 14.
    E. Khamis, M.N. Moussa, E.S.H. El-Ashry and A.K. Ibrahim, Adsorption Sci. & Technol. 13 (1996) 197.Google Scholar
  15. 15.
    E. Khamis, Corrosion 46 (1990) 476.Google Scholar
  16. 16.
    I. Epelboin, M. Keddam and H. Takenouti, J. Appl. Electrochem. 2 (1972) 71.Google Scholar
  17. 17.
    V.P. Grigorev and V.U. Eklik, Prot. Met. 4 (1968) 517.Google Scholar
  18. 18.
    V.P. Grigorev and O.A. Osipov, 3rd European Symposium on ‘Corrosion Inhibitors’, Ferrara, Italy (1970), p. 473.Google Scholar
  19. 19.
    L.A. Antropov and Y.A. Suvgira, Prot. Met. 3 (1967) 597.Google Scholar
  20. 20.
    E. Khamis, F. Bellucci, R. Latanision and E. El-Ashry, Corrosion 47 (1991) 677.Google Scholar
  21. 21.
    A. El-Awady, B. AbdEl-Nabey and Aziz, J. Electrochem. Soc. 135 (1992) 2149.Google Scholar
  22. 22.
    A. El-Awady, B. Abd El-Nabey and G. Aziz, M. Khalifa and H. Al-Ghamdy, Int. J. Chem. 1 (1991) 169.Google Scholar
  23. 23.
    A. Frignani, G. Trabanelli, F. Zicchi and M. Zucchini, Proc. 5th European Symposium on ‘Corrosion Inhibitors’, Ferrara, Italy (1980) 1185.Google Scholar
  24. 24.
    I. Epelboin, M. Keddam and H. Takenouti, J. Appl. Electrochem. 2 (1972) 71.Google Scholar

Copyright information

© Kluwer Academic Publishers 2002

Authors and Affiliations

  1. 1.Chemistry Department, Faculty of ScienceCairo UniversityEgypt
  2. 2.Chemistry Department, Faculty of ScienceAlexandria UniversityEgypt
  3. 3.College of Science, Chemistry DepartmentKing Saud UniversityKSA

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